The top after-market NASDAQ losers Thursday were: Layne Christensen, Anthera Pharmaceuticals, UTi Worldwide, Wet Seal, Micron Technology, Cepheid, Crocs, Alkermes, Stewart Enterprises and Spreadtrum Communications.

Layne Christensen Co. (LAYN) stock slumped 8.6 percent to $20.50 in post market session. The company expects fourth quarter adjusted net loss to be in a range of $70 to $80 million or $3.59 to $4.07 per share. The company also expects fiscal 2012 earnings to be in a range of $31 to $32 million or $1.59 to $1.64 per share compared to analysts’ estimation of $1.89 per share.

Anthera Pharmaceuticals, Inc. (ANTH) stock slumped 6.83 percent to a 52-week low of $2.32 in post market trading. The company stock slumped more than 12 percent in regular trading.

UTi Worldwide Inc. (UTIW) stock slumped 6.10 percent to $16.00 in post market trading. Its fourth quarter net profit declined to $12.4 million or $0.12 per share from $14.5 million or $0.14 per share in the same period a year-ago. Revenue rose to $1.153 billion from $1.145 billion in the same period a year-ago, but fell short of analysts’ estimation of $1.2 billion.

Wet Seal, Inc. (WTSLA) stock plunged 4.23 percent to $3.40 in aftermarket session. Its fourth quarter net profit declined to $1.1 million or $0.01 per share from $5.3 million or $0.05 per share in the same period a year-ago. Wet Seal also expects first quarter earnings to be in a range of $0.02 to $0.04 per share on revenues of $148 and $150 million compared to analysts’ estimation of $0.05 per share on revenue of $153.67 million.

Micron Technology, Inc. (MU) stock declined 3.21 percent to $8.43 in aftermarket session. The company swung to second quarter net loss of $224 million or $0.23 per share compared to net profit of $72 million or $0.07 per share in the same period a year-earlier. Cepheid (CPHD) stock fell 2.99 percent to $41.21 in aftermarket session. The stock has a 52-week low of $26.09, a 52-week high of $45.00 and $2.77 billion in market capitalization.

Crocs, Inc. (CROX) stock declined 2.7 percent to $20.17 in aftermarket session.

Alkermes plc. (ALKS) stock fell 2.35 percent to $16.19 in post market trading. The company stock gained more than 2 percent in regular trading after analysts at Jefferies Group re-affirmed “buy” rating on shares of Alkermes.

Stewart Enterprises, Inc. (STEI) stock fell 2.2 percent to $5.77 in post market trading session.

Spreadtrum Communications, Inc. (SPRD) stock declined 1.76 percent to $15.10 in aftermarket trading session.